Al2O3 Interface Engineering of Germanium Epitaxial Layer Grown Directly on Silicon

作者：Tan Yew Heng^*; Yew Kwang Sing; Lee Kwang Hong; Chang Yao Jen; Chen Kuan Neng; Ang Diing Shenp; Fitzgerald Eugene A; Tan Chuan Seng

来源：IEEE Transactions on Electron Devices, 2013, 60(1): 56-62.

DOI：10.1109/TED.2012.2225149

• Germanium (Ge)
• interface state density
• interfacial layer
• oxide

The quality of germanium (Ge) epitaxial film grown directly on silicon (Si) substrate is investigated based on the electrical properties of a metal-oxide-semiconductor capacitor (MOSCAP). Different thermal cycling temperatures are used in this study to investigate the effect of temperature on the Ge film quality. Prior to high-k dielectric deposition, various surface treatments are applied on the Ge film to determine the leakage current density using scanning tunneling microscopy. The interface trap density (D-it) and leakage current obtained from the C-V and I-V measurements on the MOSCAP, as well as the threading dislocation density (TDD), show a linear relationship with the thermal cycling temperature. It is found that the Ge epitaxial film that undergoes the highest thermal cycling temperature of 825 degrees C and surface treatment in ultraviolet ozone, followed by germanium oxynitride (GeOxNy) formation, demonstrates the lowest leakage current of similar to 2.3 x 10(-8) A/cm(2) (at -2 V), D-it similar to 3.5 x 10(11) cm(-2)/V, and TDD %26lt; 10(7) cm(-2).

• 出版日期2013-1
• 单位南阳理工学院